now use fgets(STDIN) to read the input. Creates connections pretty quick, works like a charm.Writing can be done using the STDOUT, or just echo. Be aware that you're completely bypassing the webserver and thus certain variables will not be available.

[ Editor's Note: There is a way to know. All response headers (from both the final responding server and intermediate redirecters) can be found in $http_response_header or stream_get_meta_data() as described above. ]

If you open an HTTP url and the server issues a Location style redirect, the redirected contents will be read but you can't find out that this has happened.

So if you then parse the returned html and try and rationalise relative URLs you could get it wrong.

While writing to error stream, error_log() function comes as a shorthand to writing to php://stderr . This function also allows writing to web server log when running through a web server such as apache.

For php://filter the /resource=foo part must come last. And foo needs no escaping at all.php://filter/resource=foo/read=somefilter would try to open a file 'foo/read=somefilter' while php://filter/read=somefilter/resource=foo will open file 'foo' with the somefilter filter applied.

Be aware of code injection, folks - like anything else you take from the user, SANITISE IT FIRST. This cannot be stressed enough - if I had a dollar for each time I saw code where form input was taken and directly used (by myself as well, I've been stupid too) I'd probably own PHP. While using data from a form in a URL wrapper is asking for trouble, you can greatly minimise the trouble by making sure your inputs are sane and not likely to provide an opening for the LulzSec of the world to cause havoc.

In trying to do AJAX with PHP and Javascript, I came upon an issue where the POST argument from the following javascript could not be read in via PHP 5 using the $_REQUEST or $_POST. I finally figured out how to read in the raw data using the php://input directive.

The stream php://temp/maxmemory:$limit stores the data in memory unless the limit is reached. Then it will write the whole content the a temporary file and frees the memory. I didnt found a way to get at least some of the data back to memory.

The correct mime type for this should be "application/octet-stream" however if you set this or any other recognised mime type other than "multipart/form-data" on your POST then $HTTP_RAW_POST_DATA is populated and the memory is consumed anyway.

Setting the mime type to "multipart/form-data" raises “PHP Warning: Missing boundary in multipart/form-data POST data in Unknown on line 0” however it seems to work without a problem.

The use of php://temp/maxmemory as a stream counts towards the memory usage of the script; you are not specifying a new memory pool by using this type of stream.As noted in the documentation however, this stream type will start to write to a file after the specified maxmemory limit is exceeded. This file buffer is NOT observed by the memory limit.This is handy if you want your script to have a reasonably small memory limit (eg 32MB) but but still be able to handle a huge amount of data in a stream (eg 256MB)

The only works if you use stream functions like fputs(); if you use $buffer .= 'string'; or $buffer = $buffer . 'string'; you're calling your stream data back into PHP and this will hit the limiter.